diff --git a/src/protocol_misc.c b/src/protocol_misc.c
index de426c78..95bd322e 100644
--- a/src/protocol_misc.c
+++ b/src/protocol_misc.c
@@ -164,7 +164,7 @@ bool send_sptps_tcppacket(connection_t *c, const char* packet, int len) {
 	if(2.0 * c->outbuf.len / (float)maxoutbufsize - 1 > (float)rand()/(float)RAND_MAX)
 		return true;
 
-	if(!send_request(c, "%d %hd", SPTPS_PACKET, len))
+	if(!send_request(c, "%d %d", SPTPS_PACKET, len))
 		return false;
 
 	send_meta_raw(c, packet, len);